CVE-2026-20896 (GCVE-0-2026-20896)

Vulnerability from cvelistv5 – Published: 2026-07-03 20:19 – Updated: 2026-07-07 17:00
VLAI
Title
Gitea Docker image trusts spoofable reverse-proxy headers by default
Summary
Gitea Docker image versions up to and including 1.26.2 use REVERSE_PROXY_TRUSTED_PROXIES=* by default, allowing any source IP to impersonate a user when reverse-proxy authentication headers such as X-WEBAUTH-USER are enabled.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-06 19:03 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Gitea Gitea Open Source Git Server Affected: 0 , ≤ 1.26.2 (semver)
guessed Create a notification for this product.
Credits
Joshua Martinelle (Tenable) rz1027
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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